Carrying scraper



Apr-i129, 1941. J, Low '9 2,239,997

CARRYING SCRAPEB 7 Filed Feb. 1, 1939 3 Sheets-Sheet 1 m] i I qINVENTOR. c/O/IAKJ 014" ATTORNEY.

April 29, 1941; .1. J. LOW

CARRYING SCRAPER Filed Feb. 1, 1939 3 Sheets-Sheet 2 f/QMWMV INVENTOR.cfa/m J10 N l g Y I \n x v wwc A mb.b\ l a ATTORNEY.

April 29,1941. J w 2,239,967

CARRYING SCRAPER Filed Feb. 1. 19:59 s Sheets-Sheet s INVENTOR.

c/0///V J Low ATTORNEY.

Patented'Apr. 29, 1941 UNITED STATES PATENT OFFICE cnanme semen,

John J. Low, Los Anzeles, Calm,

assignor to Ray- Brnnner Steel Products, Inc., a corporation of DelawareApplication February 1, 1939, Serial No. 254,021

1 Claims.

My invention relates to carrying scrapers of the character embodied inmy co pending application Serial No. 217,658, .filed July 6, 1938,wherein is embodied a bowl, an apron at the front of the bowl, onejector for ejecting earth from the bowl, and a mechanism operativelyconnecting the ejector to the apron by which actuation of the ejector iseffected in such manner that its movement from a retracted position atthe top of the bowl to an advanced position at the front of I the bowlin ejecting earth therefrom, is initiated only after the apron hasreached such an open position with respect to the bowl that it does notobstruct or interfere with discharge of earth from the bowl by theejector.

It is a purpose of my present invention to provide a carrying scraperembodying a mechanism for actuating the ejector which functions to applyto the ejector a force suflicient to move the earth in a fully loadedbowl for initiating discharge of the earth therefrom; to decrease theapplied force as the load is decreased by reason of its discharge; andto increase the rate of travel of the ejector as'the applied force isdecreased so as to so accelerate movement of the ejector that a finalthrowing of the remaining earth from. the bowl is effected By operatingthe ejector in this manner, a more rapid and complete discharge of earthfrom the bowl is secured and without the parts of the mechanism beingsubjected to any fundue stresses or strains, and through the applicationof a minimum pull on the cable or other medium for operating themechanism.

It is also a purpose of my invention to provide a carrying scraperembodying a mechanism for operating theearth ejector in the manner abovedescribed and which is devoid of springs or any other devices that maycomplicate and weaken the structural simplicity and ruggedness by whichmy, mechanism is in part characterized.

I will describe only one form 6f carrying scraper embodying my inventionand will then point I out the novel features in claims.

Figure 1 is a view showing in top plan one form of carrying scraperembodying my invention.

Fig. 2 is a view showing the carrying scraper in side elevation andearth scraping position.

Fig. 3 is a view similar to Fig. 2, but partly in vertical section andwith the bowl in earth carrying position.

In carrying out my invention, I provide a main frame A having inclinedside beams I5, I5 connected at their forward ends by a cross beamdepends a standard 88 supporting a swivel wheel truck 19 having a drawbar 20 adapted for con-- if nection to a tractor. A second frame B ispivoted on the frame A between the side beams is for movement about atransverse and horizontal axis. This frame B low vertical movement ofthe frame comprises an upper rigid structure having upper side beams-2|,2i and a rear cross beam 22. Rear and front comer beams 23, 23 and 24,24depend from the side beams 2!. These corner beams are rigidly connectedto the side beams and to each other by lower side beams 25, 25.

The rear ends of the beams 25 are rigidly connected by a cross beam25,-while to the beams 22 and 28 rigid frames 2? audit, respectively,are securedto coact with an axle 29 and wheels 30 in forming a rearwheel truck for the scraper.

An axle 88 is mounted in and extendsthrough the frames 2i and 28, whileon the ends of the axle the rear ends of beams It are pivoted toalrelative to the frame A and about the axle ti asa center. The frame Bhas secured therein a bowl C which includes a pair of side plates 32between which is secured a combined bottom and back end plate 33 whichis curved about an axis E and terminates at its forward end in a blade35.

For actuating the frame B to lift the bowl 0 from scraping position tocarrying position the following mechanism may be provided. A pair ofturn-buckles 35 are secured to the corner beams 23 and to a pair of rods35, with the latter in turn pivotally connected to a pair of arms tifixed to the opposite ends of a shaft 38 jouraled in bearings 39 securedto the cross beam 56. Fixed'to the shaft 38 at a point between thosebearings 39; at the center of the shaft, are a pair of relative. longarms so disposed substantially at right angles to the shorter arms 31.Sheaves ii are mounted between the free ends of the arms 69, while acompanion set of sheaves 42 are "supported on a, shaft 63 carried by ablock 63a senection to a, tractor.

l6 having a forward extension H from which From the precedingdescription it will be clear that by pulling on the cable 44 the arms 40are rocked forwardly to rotate the shaft 38 and thus lift the arms 3'!to elevate the rods 36, thereby elevating the front end of the frame 13to raise the bowl- 0.

I by a blade 58 from For retaining earth in the bowl C after load= ingthereof, an apron D is provided which includes a pair of upwardlyextending side beams M to which are secured downwardly extending armsd'la pivoted on trunnions 38 secured to the beams 2 so that the apron ismovable between the sides of the frame B to occupy open and closedpositions with respect to the bowl.

The mechanism for lifting the apron D comprises a set of sheaves 69carried in a block &-

secured to the apron, and another set of sheaves 5i carried on a crossbeam 52 secured to the forward ends of the side beams 2! by upstandingbeams 53;. A cable 54 is extended around the two sets of sheaves withone end secured to the sheaves 49 and the other end extended forwardlyover a sheave 55 on the shaft 43. From this point the cable proceedsdownwardly beneath a sheave 56 on the shaft 46, from which it leads tothe tractor. Manifestly, the cable is operable to lift the sheaves 49thereby swinging the apron D upwardly about the trunnions 48 as acenter.

4 For discharging all earth from the bowl after the apron has been movedto an unobstructed position, an ejector-F is provided. This ejectorcomprises side arms 51 bridged at their rear ends which rises aninclined plate 59 spanning the arms and secured to a frame comprisingside bars 60 bolted to the side arms, and vertical bars 5| secured tothe side bars and connected at their upper ends by a cross bar '52. Inthe operation of the ejector the blade 58. cuts the earth free of thebowl plate 33, while the plate 59 pushes the earth forwardly and awayfrom the plate 33 so that it cannot pack and interfere with the properoperation of the ejector in its earth ejecting movement.

The forward ends of the arms 51 are provided with trunnions 63 joumaledin bearings 34 fixed to the beams 2!. These trunnions constitute theposition through operation of the cable 53," the pivots W are movedupwardly and rearward about the pivots it as a center. Under this motionthe links'lisare swung ppwardly about the pivots is to the positionshown in dot and dash lines, there being no appreciable movement of thelevers l, and hence no appreciable movement of the ejector. Thus, theapron can be opened to the dot and dash'line position without movementof the ejector thereby permitting that earth which is free to gravitatefrom the bowl and apron to do so. i

By now elevating the apron to the dash line position, which is the fullopen position thereof, the links 15 now exert a lift on the levers I0moving them to the dash line position and thereby pulling the links 12upwardly to the dash line position. Under this elevating movement 0! thelinks 12 the arms 51 are swung downwardly about the axis E as a centerthereby advancing the ejector downwardly and forwardly in the bowl.

By reason of the relation of the pivots of the links, arms and levers toeach other the effective leverage of the links 15 is greatest during thefirst part of their movement upwardly from the dot and dash lineposition, such leverage decreasing as the links approach their uppermostposition. This leverage being at all times transmitted to the ejectorthrough the links I2 and the cranks 15, it becomes apparent that thepower or moving force applied to the ejector by the mechanism, isgreatest at the beginning of its movement from retracted position,decreasing continuously until the ejector reaches its advanced position.It will be apparent, also, that as the eflective leverage decreases therate of movement of the ejector increases, and thus through my mechanismmotion of the ejector axis E about which the ejector F swin s, with theblade 58 maintaining a position parallel to the W1 plate 33.

For operating the ejector, the elevating motion of the'apron is utilizedthrough a mechanism which comprises two sets of links-situated atopposite sides of the bowl, and as they are identical in construction, adescription of one willsufilce for both.

A two part bracket 69 rises from the side beam 2i and in which the upperend of a lever it is pivotally mounted by means of a pin ii.

78, pins ii and it being provided for the purpose.

To brace the apron beams 5'5, 6? and provide a substantial mounting forthe pins ll, ll, a tubular beam it extends between the apron beams andis provided with upstanding ears 86, so in which the inner ends'of thepins "ii are mounted.

, The operation of the ejector actuating mechanism will be understoodfrom a consideration of Fig". 3. With the apron in closed position asshown in solid lines, the ejector occupies retracted position at the topof the bowl, while the twosets of links comprising the ejector actuatingmechanism are in the solid line positions shown. Upon lifting the apronto the dot and dash line from retracted to advanced position isaccelerated. The design of my mechanism is such that for substantiallyhalf of the forward movement of the ejector the effective leverage and,hence, the applied power, is at substantially a constant maximum.Therefore, the rate of movement of the ejector must be of necessity,substantially constant. Beyond this half-way point the eflectiveleverage decreases rapidly thereby decreasing the power appliedaccordingly, but rapidly increasing the rate of movement of the ejector.

In actual practice, the advantages provided by my mechanism will beapparent from the following. Assuming that the apron has just been movedto the open position shown in dot and dash lines in Fig. 3 and theloaded bowl tilted, a certain part of the earth will gravitate from thebowl. Continued opening of the apron at a constant rate of movement nowsets the ejector actuating mechanism into operation causing the ejectorto move relatively slowly and at substantially a constant rate. It isduring this period of movement that the maximum eifective leverage andhence the maximum power of which the mechanism is capable, is applied tothe ejector. As it is at this time that the earth load is the greatest,the mechanism moves the ejector with a force sufilcient to pull thatmaximum load forwardly in the bowl,

As the earth advances it is discharged from the bowl lessening the loadand hence the resistance offered to movement of the ejector.. Meanwhile,the mechanism is functioning to decrease the power or force applied tothe ejector and to a degree corresponding substantially to the decreasein load. Inasmuch as the speed of travel of the ejector increases as thepower applied decreases, movement of the ejector is accelerated to suchan extent that in the final part of its movement the earth remaining inthe bowl is projected or thrown from the bowl. Thus, in the finaladvanced position of the ejector all earth has been swept from the bowl.

From this mode of operation of the ejector it becomes manifest thataccording as the earth load in the bowl decreases the power applied tothe ejector decreases, while the rate of movement of the ejectorincreases.

Upon returning the apron to closed position or to partly open positionfor scraping as shown in Fig. 2, reverse movements of the link mechanismoccurs to return the ejector to retracted position at the top of thebowl.

Although I have herein shown and described only one form of carryingscraper embodying my invention, it is to be understood that variouschanges and modifications may be made herein without departing from thespirit of my invention and the spirit and scope of the appended claims.

I claim:

1. A scraper, comprising; a bowl; an apron having rearwardly extendingarms pivoted on the bowl; an ejector having arms pivoted on the bowl toswing about an axis; cranks on the ejector arms projecting forwardlyfrom said axis; levers pivoted on the bowl above the cranks; linksconnecting the forward ends of the levers to said cranks; and otherlinks connecting the apron to the levers at a point in the rear of theconnection of the levers with the first mentioned links.

2. A scraper, comprising; a bowl; an apron at the front of the bowlmovable to occupyopen and closed positions with respect to the bowl; anejector movable in the bowlto or from aretracted position at the top ofthe bowl to or from an advanced position at the front of the bowl; and amechanism operatively connecting the apron and ejector for advancing 'orretracting the ejector according as the apron'is open or closed, saidmechanism including at least one set of elements each set comprising alever mounted on the bowl, a link connecting one side curvature of saidbowl wall; an earth ejector carried by said arms to swing forwardlythrough the bowl; an apron pivoted on the bowl to swing about an axisspaced from the pivotal axis of the arms; levers pivoted to the bowl;links pivoted to the arms and to the levers; other links pivoted to theapron and to the levers; and means for moving the apron, whereby thelevers and links coact to move the ejector forwardly at a progressivelyincreasing speed.

4. In a carrying scraper; a bowl; arms pivoted on the bowl; an earthejector carried by said arms to swing forwardly through the bowl; an

apron pivoted on the bowl; levers pivoted to the of the ejector to thelever, and a second link connecting the corresponding side of the apronto the lever at a point between the first mentioned link and the lever.

3. In a carrying scraper; a bowl having a circularly curved back andbottom wall; arms pivoted on the bowl substantially at the center ofbowl; links pivoted to the arms and to the levers; other links pivotedto the apron and to the levers; and means for moving the apron, wherebythe levers and links coact to swing the ejector forwardly through thebowl.

5. In a carrying scraper; a bowl; arm's pivoted on the bowl; an earthejector carried by said arms to swing forwardly through the bowl; anapron pivoted onthe bowl; levers pivoted to the bowl; links pivoted tothe arms and to the levers; other links pivoted to the apron and to thelevers at points nearer to the pivots of levers than the pivots of thefirst mentioned links; and means for moving the apron, whereby thelevers and links coact to actuate the ejector.

6.111 a carrying scraper; a bowl; arms pivoted on the bowl; an earthejector carried by said arms to swing forwardly through the bowl; anapron pivoted on the bowl; links pivoted to the arms at points forwardlyof the arm pivots; levers pivoted to the bowl above and rearwardly v ofthe arm pivots, and to the links; other links pivoted to apron and tothe levers between the lever pivots and the pivots of the firstmentioned links' to the levers; and means for moving the apron wherebythe levers and links coact to swing the ejector forwardly through thebowl at a progressively increasing speed.

7. In a carrying scraper; a'bowl; arms pivoted on the bowl; an earthejector carried by said arms to swing forwardly through the bowl; anapron pivoted on the bowl; levers pivoted to the bowl above andrearwardly of the arm pivots;

links pivoted to the arms forwardly of the arm pivots and pivoted to thelevers; other links pivoted to the apron and to the levers between thelever pivots and the pivots of the first mentioned links; and means forlifting the apron to open position in respect to the bowl, whereby thelevers and links coact to swing the ejector forwardly through the bowlat a progressively increasing speed after the apron has been lifted to apredetermined open position.

JOHN J. LOW.

